> -----Original Message----- > From: David Woodhouse [mailto:dwmw2@xxxxxxxxxxxxx] > Sent: Thursday, May 04, 2017 6:22 AM > To: Deucher, Alexander; 'Joerg Roedel'; Bjorn Helgaas > Cc: linux-pci@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Daniel Drake; > Samuel Sieb; Joerg Roedel > Subject: Re: [PATCH v2] PCI: Add ATS-disable quirk for AMD Stoney GPUs > > On Fri, 2017-04-07 at 16:46 +0000, Deucher, Alexander wrote: > > > > > > -----Original Message----- > > > From: Joerg Roedel [mailto:joro@xxxxxxxxxx] > > > Sent: Friday, April 07, 2017 10:32 AM > > > To: Bjorn Helgaas > > > Cc: linux-pci@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Daniel > Drake; > > > Deucher, Alexander; Samuel Sieb; David Woodhouse; Joerg Roedel > > > Subject: [PATCH v2] PCI: Add ATS-disable quirk for AMD Stoney GPUs > > > > > > From: Joerg Roedel <jroedel@xxxxxxx> > > > > > > ATS is broken on this hardware and causes IOMMU stalls and > > > system failure. Disable ATS on these devices to make them > > > usable again with IOMMU enabled. > > > > > > Note that the commit in the Fixes-tag is not buggy, it > > > just uncovers the problem in the hardware by increasing > > > the ATS-flush rate. > > > > > > Fixes: b1516a14657a ('iommu/amd: Implement flush queue') > > > Signed-off-by: Joerg Roedel <jroedel@xxxxxxx> > > Acked-by: Alex Deucher <alexander.deucher@xxxxxxx> > > Alex, are you able to confirm that it is *only* the device with PCI ID > 0x98e4 which has this problem, or (more likely) come up with an > exhaustive list? Thanks. It's just Stoney, that is the only ID. ATS is validated on the other GPU parts. Alex > > We'll want the same blacklist in Xen too, won't we? > > > > > > > --- > > > drivers/pci/quirks.c | 19 +++++++++++++++++++ > > > 1 file changed, 19 insertions(+) > > > > > > diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c > > > index 6736836..7cbe316 100644 > > > --- a/drivers/pci/quirks.c > > > +++ b/drivers/pci/quirks.c > > > @@ -4634,3 +4634,22 @@ static void quirk_no_aersid(struct pci_dev > *pdev) > > > DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2031, > > > quirk_no_aersid); > > > DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2032, > > > quirk_no_aersid); > > > DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2033, > > > quirk_no_aersid); > > > + > > > +#ifdef CONFIG_PCI_ATS > > > +/* > > > + * Some devices have a broken ATS implementation causing IOMMU > stalls. > > > + * Don't use ATS for those devices. > > > + */ > > > +static void quirk_disable_ats(struct pci_dev *pdev) > > > +{ > > > + /* > > > + * Set pdev->ats_cap = 0 to make pci_enable_ats() bail out > > > + * early. > > > + */ > > > + dev_info(&pdev->dev, "QUIRK: Disabling ATS"); > > > + pdev->ats_cap = 0; > > > +} > > > + > > > +/* AMD Stoney platform GPU */ > > > +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATI, 0x98e4, > quirk_disable_ats); > > > +#endif /* CONFIG_PCI_ATS */ > > > -- > > > 1.9.1
